1. Field of the Invention
The present invention relates to a collision detecting device mounted on automobiles or the like and adapted to actuate a safety device such as an air bag upon detection of a collision of the automobile or the like.
2. Description of the Prior Art
One of the known collision detecting devices is shown in the specification of U.S. Pat. No. 4,188,517. This known collision detecting device incorporates a rotary member having an eccentric centroid, two cams adapted to rotate in synchronism with the rotary member and an electric contact mechanism associated with the cams and adapted to being actuated by the rotation of the cams to generate a signal.
This known device is electrically connected between a seat occupant protecting device mounted on the automobile and an electric power supply. In the event of a collision, the collision detecting device produces a signal to supply the protecting device with an electric current thereby actuating the latter. In this known collision detecting device, the collision is detected through the detection of mechanical displacement of a weight (rotary member) caused by an impact as a result of the collision. More specifically, a cylindrical housing is accommodated by a case which is closed at its one end by an end plate, and the aforementioned rotary member which rotates in response to the collision impact is housed by this housing. The end openings of the housing are closed by a lid and a base, respectively, and an elastic member is disposed between the case and the lid.
This collision detecting device, however, is too complicated in construction and requires an impractically large number of steps for assembling, although it can generate the collision signal without fail.